diff options
Diffstat (limited to 'libbutl/sha256.cxx')
-rw-r--r-- | libbutl/sha256.cxx | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/libbutl/sha256.cxx b/libbutl/sha256.cxx index be29871..694b331 100644 --- a/libbutl/sha256.cxx +++ b/libbutl/sha256.cxx @@ -122,7 +122,7 @@ namespace butl string f; f.reserve (n + 31); - for (size_t i (0); i < n; ++i) + for (size_t i (0); i != n; ++i) { char c (s[i]); if (!isxdigit (c)) @@ -138,7 +138,7 @@ namespace butl } string - fingerprint_to_sha256 (const string& f) + fingerprint_to_sha256 (const string& f, size_t rn) { auto bad = []() {throw invalid_argument ("invalid fingerprint");}; @@ -146,9 +146,16 @@ namespace butl if (n != 32 * 3 - 1) bad (); + if (rn > 64) + rn = 64; + string s; - s.reserve (64); - for (size_t i (0); i < n; ++i) + s.reserve (rn); + + // Note that we continue to validate the fingerprint after the result is + // ready. + // + for (size_t i (0); i != n; ++i) { char c (f[i]); if ((i + 1) % 3 == 0) @@ -161,7 +168,8 @@ namespace butl if (!isxdigit (c)) bad (); - s += lcase (c); + if (s.size () != rn) + s += lcase (c); } } |